Answer:
X = 3625/125 = 29
Step-by-step explanation:
43.25 = $7 + 1.25*X where X is the number of minutes he used the trampoline
36.25 = 1.25* X <--- subtracts 7 from both sides
3625 = 125 X <--- multiplies both sides by 100 to clear away the decimals